I think this is from the Yoast SEO plugin, but not positive. It updated this morning, and I only noticed it today.
Every new post and draft (and if I update an already published post) has a custom field variable name
yst_is_cornerstone showing with an empty value. It won't delete. Deleting doesn't do anything. Changing the value and name and hitting update results in it being re-added in addition to whatever I tried changing it to.
I'm worried it is some type of infection because the only Google result for
yst_is_cornerstone brings up a sketchy page.
Anyone know what this is / how to remove it?
Update: I just did a database query, and the
yst_is_cornerstone only appears in the meta of new posts, it hasn't been added to every single post. But each time I update a post or create a new one, it is added.
Update 2: The field doesn't save values. Anything inputted disappears as soon as it is saved.